Quick action fastener assembly

ABSTRACT

A fastener assembly for joining a panel to a sub-panel comprising a receptacle assembly having a threaded stud secured to the undersurface of the sub-panel. The assembly includes a bolt having an enlarged head at one end and a nose at the other end. The panel has a countersunk opening aligned with an opening in the sub-panel. The bolt is threaded for threaded engagement to the stud. The body of the bolt includes a plurality of spaced grooves extending longitudinally along the outer surface of the bolt body. A retainer surrounds the bolt body having spaced ears riding in the grooves and a stop ring in a groove adjacent the nose of the bolt stops the downward movement of the retainer. 
     In this manner, the bolt may be disposed in the countersunk opening in the panel with the retainer on the blind side of the panel and the stop ring preventing movement of the retainer off of the bolt body thus retaining the bolt to the panel. The bolt can remain in the up or extracted portion while the panel is being attached to the installation. A plate is provided on the underside of the panel trapping the retainer between the plate and the panel. The stop ring prevents downward movement of the bolt when in a hold out position with respect to the panel and restraining meaning on the bolt prevents inward movement of the bolt when in the hold out position with respect to the panel.

This is a divisional of co-pending application Ser. No. 07/196,900 filedon May 17, 1988, now U.S. Pat. No. 4,865,500 which in turn was acontinuation of Application No. 06/927,320, filed Nov. 4, 1986, nowabandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to quick action fasteners; and, more particularly,to improved quick action fasteners for panels of aircraft or the like.

2. Description of the Prior Art

Quick action fasteners are well known in the art. One such fastener isdescribed in U.S. Pat. No. 2,991,816 to Harbison et al. These fastenerscomprise a bolt body of stepped diameters and are used in aircraftpanels having holes of certain diameters. These fasteners can be shiftedin the panel holes, due to their stepped diameters, to compensate forslight misalignment of the holes in an abutting panel and subpanel.

These prior art fasteners consist of a bolt having a retaining springadapted to retain the bolt to a panel. The bolt is adapted to bethreaded to a receptacle assembly mounted to a sub-panel. When torque isapplied to the bolt, it is threaded to a stud in the receptacle assemblywhich draws the sub-panel to the panel and locks them together. When itis desired to unlock the panel from the sub-panel, the bolt is unscrewedfrom engagement with the stud and will be retained to the panel whenfree of the stud.

The retaining spring for the foregoing prior art bolt assembly fits intoa countersunk hole in the subpanel. These springs must expand andcontract about the varying diameter sections of the bolt body. This canresult in wear of the springs and fatigue of the same whereby they maycome off the bolt body and be sucked into the aircraft engine causingdamage to the aircraft. Of course, once the spring is free of the boltbody, the bolt can vibrate out of the panel hole and also be lost andsucked into the aircraft engine. In my co-pending application Serial No.(Docket No. 63-228), John A. Duran, inventor, and commonly assigned, Idescribe a panel fastener that can be used in preexisting aircraft paneland sub-panel holes while providing for some misalignment of the holeswithout danger of loss of components of the fastener assembly. Thefastener assembly has a retainer retaining the bolt of the fastenerassembly, which bolt has a shank of varying diameters, to a panelwherein the retainer does not have to expand and contract as it passesover the varying diameters of the bolt body. There are instances whereit is desired to have the bolt of the panel fastener remain in the up orextracted position and hold it there while the panel is being attachedto the installation, such as an aircraft. There is need for such panelfastener which retains the bolt in the extracted position.

SUMMARY OF THE INVENTION

It is an object of this invention to provide an improved quick actionfastener assembly having a retainer retaining a bolt with a shank ofvarying diameters to a panel without expansion and contraction of theretainer as it passes over the shank of the body of the bolt and whichallows the retainer to be trapped to the panel and holds the bolt in anup or extracted position.

These and other objects are preferably accomplished by providing afastener assembly comprising a receptacle assembly having a threadedstud secured to the undersurface of the sub-panel. The assembly includesa bolt having an enlarged head at one end and a nose at the other end.The panel has a countersunk opening aligned with an opening in thesub-panel.

The body is threaded for threaded engagement to the stud. The body ofthe bolt includes a plurality of spaced grooves extending longitudinallyalong the outer surface of the bolt body. A retainer surrounds the boltbody having spaced ears riding in the grooves and a stop ring in agroove adjacent the nose of the bolt stops the downward movement of theretainer. A plate is provided on the underside of the panel trapping theretainer between the plate and the panel. The stop ring preventsdownward movement of the bolt when in a holdout position with respect tothe panel and restraining means on the bolt prevents inward movement ofthe bolt when in the hold out position with respect to the panel. In oneembodiment, the stop ring and restraining member may be a singleelement. In this manner, the bolt may be disposed in the countersunkopening in the panel with the retainer on the blind side of the paneland the stop ring preventing movement of the retainer off of the boltbody thus retaining the bolt to the panel. The bolt can remain in the upor extracted position while the panel is being attached to theinstallation.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an exploded view of a fastener assembly in accordance with theteachings of the invention;

FIG. 2 is a vertical sectional view of the fastener assembly of FIG. 1installed in a panel and abutting sub-panel;

FIG. 3 is a vertical view partly in section of the bolt of FIG. 1 withthe resilient ring, retainer and stop ring mounted thereto;

FIG. 4 is a view taken along lines IV--IV of FIG. 3;

FIG. 5 is a perspective view of one element of the fastener assembly ofFIGS. 1 to 4;

FIG. 6 is a view taken along lines VI--VI of FIG. 3;

FIG. 7 is a view taken along lines VII--VII of FIG. 2;

FIG. 8 is a partial view similar to FIG. 3 showing another step in thefunctioning thereof;

FIG. 9 is a view similar to FIG. 3 showing a modification of the boltand retainer thereof;

FIG. 10 is a perspective view of a modified retaining ring used on thebolt of FIG. 9;

FIGS. 11 and 12 are views similar to FIGS. 8 and 2, respectively,showing two steps in the functioning of the apparatus of FIG. 9;

FIG. 13 is a vertical view of another modification of the bolt andretainer of FIGS. 1 to 8; and

FIG. 14 is a perspective view of one element of the apparatus of FIG.13; and

FIGS. 15 and 16 are views similar to FIGS. 11 and 12, respectively,illustrating two steps in the functioning of the apparatus of FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1 of the drawing, there is shown a fastenerassembly 10 comprising a bolt 11 adapted to mate with a receptacleassembly 12. Receptacle assembly 12 is comprised of a receptacle bracketor basket 13, a barrel 14 and an externally threaded stud 15. As seen inFIG. 2, the lower end 16 of barrel 14 is crimped about the base 18 ofstud 15 to engage the stud 15 and connect the barrel 14 thereto. As seenin FIG. 1, the stud 15 has a boss 100 with flattened areas 101, 102 (seealso FIG. 7). As seen in FIG. 2, barrel 14 has an inwardly extendingperipheral wall 103 configured similarly to boss 100 (FIG. 7). This isan anti-rotation feature preventing stud 15 from rotating within barrel14 thereby allowing the stud 15 and barrel 14 to mate and lock and actas one unitary element. Barrel 14 also includes tabs 19 which areinserted in a pair of slots 20, formed in basket 13, thereby connectingthe barrel 14 to basket 13. Slots 20 are circumferentially greater inlength than the width of tabs 19 thereby permitting the barrel 14 andstud 15 to rotate to a limited degree with respect to basket 13. Basket13 is secured to substructure 20 (FIG. 2) by any suitable means, such asrivets 21. Although receptacle assembly 12 and basket 13 have beendescribed as an assembly of individual components, obviously a singleelement may be used.

Bolt 11 is shown in FIG. 2 in its disengaged and withdrawn position withrespect to panel 22.

Bolt 11 includes a blunt nose 23, an annular groove 24 adjacent nose 23and a generally cylindrical lower shank portion 25 (FIG. 2). Bolt 11also includes an upper generally cylindrical shank portion 26 of anouter diameter substantially greater than the outer diameter of lowershank portion 25. A tapered portion 27 provides transition from uppershank portion 26 to lower shank portion 25. Bolt 11 has an enlarged head28 at the upper end of shank portion 26 which head 28 is tapered attapered portion 29 on its undersurface leading to shank portion 26. Head28 is adapted to abut or bear against a countersunk opening 30 (FIG. 2)in panel 22 when threaded to stud 15 as will be discussed. Countersunkopening 30 in panel 22 is aligned with an opening 31 through sub-panel20 as shown in FIG. 2. A hex socket 32 (see also FIG. 4) may be providedin head 28 as is well known in the art for receiving a suitable wrenchtherein. The interior surface 152 (FIG. 2) of bolt 11 is threaded, atthreaded portion 153.

As seen in FIGS. 1 and 6, bolt 11 includes a plurality, such as three,of longitudinally extending slots or grooves 35 to 37 extending alongthe exterior thereof longitudinally and generally parallel to thelongitudinal axis of bolt 11. These grooves 35 to 37 are preferablygenerally rectangular in cross section and may be of a depth at leastsubstantially equal to the inward extent of the three ears 38 to 40 on aflat annular washer or ring 34 as seen in FIG. 5.

As seen in FIG. 1, an annular resilient locking ring 41 is provided of adiameter adapted to pass over nose 23 of bolt 11 and snap-fit intogroove 24. The nose 23 of bolt 11 may have a terminal tapered end 42(FIG. 2) leading therein to facilitate assembly of ring 41 and guide thenose 23 of bolt 11 into the countersunk opening 30 through panel 22.

Also seen in FIG. 1 is a restraining member in the preferred form of aresilient annular O-ring 150 which is adapted to snap fit into anannular groove 151 machined or otherwise formed on the inner surface 152(FIGS. 2 and 3) of bolt 11 so that the groove 151 is only exposed on theexterior of bolt 11 where groove 151 intersects grooves 35 through 37(see FIG. 1). A counterbore 154 is provided on the blind or interiorside 155 of panel 22 for receiving ring 34 therein. A flat plate 156 isriveted, via rivets 157, or otherwise secured to the side 155 of panel22. As seen in FIG. 2, plate 156 extends from hole 158 through panel 22to a gasket 50 provided between panel 22 and sub-panel 20, as will bediscussed further hereinbelow. Thus, as seen in FIG. 2, the ring 34 istrapped between the plate 156 and the panel 22 in counterbore 154.

The assembly of the elements of FIG. 1 will now be described. Afterformation of openings 30 and 31 through panel 22 and sub-panel 20,respectively, the receptacle assembly 12 is secured to the underside ofsub-panel 20 by riveting basket 13 to panel 20 by rivets 21 passingthrough holes 44 (FIG. 1) in basket 13 and into sub-panel 20. The barrel14 and stud 15 are secured thereto as heretofore described. One or moreinwardly facing protrusions 43 may be provided on the exterior of barrel14. These protrusions 43 provide a friction lock between the internalsurface of barrel 14 and the exterior of bolt 11. Of course, anysuitable thread lock as is known in the art may be used, such as aplastic insert installed through the side of barrel 14 or protrusions onthe threads of the bolt.

Bolt 11 is now inserted through countersunk opening 30 and through hole158. Ring 150 is snap fit into groove 151 and ring 34 is mounted to bolt11 with ears 38 to 40 entering grooves 35 through 37, respectively (FIG.6). Retaining ring 41 is snap fitted over nose 23 and into groove 24 asheretofore described. Thus, ring 34 cannot move off of bolt 11 becauseof its engagement with ring 41 (ears 38 to 40 abutting against ring 41in its downwardly movement--see FIG. 3) nor move up past enlarged head29. Plate 156 is installed on panel 22. Thus, bolt 11 is trapped inopening 30 in panel 22 with ring 34 trapped between plate 156 and panel22 in counterbore 154.

Sub-panel 20 may now be brought into position abutting against panel 22and bolt 11 may be threaded to stud 15 on the receptacle assembly 12.Thus, sub-panel 20 is releasably secured to panel 22. The ring 34 ridesin grooves 35 to 37 up and down over the differing diameter sections ofbolt 11 as heretofore described.

As seen in FIG. 3, the flat washer or ring 34 is shown disposed withingrooves 35 to 37 above ring 150. Ring 34 slides over resilient ring 150(FIG. 8) and stops against the retaining ring 41. This is the positionshown in FIG. 2. In this manner, the bolt 11 remains in the up orextracted position shown in FIG. 2 while the panel 22 may be eitherabutting against panel 20, as shown in FIG. 2, or moved away therefrom,or bolt 11 may even be mounted in panel 22 prior to connection to theaircraft or other installation in which the panel 22 is mounted. Thewasher or annular ring 34 remains trapped between rings 150 and 41, asseen in FIG. 2, not only holding bolt 11 in the hold out position, butensuring it can't move back inwardly.

As seen in FIG. 9, a modified bolt 160 is shown otherwise similar tobolt 11 of FIGS. 1 to 8 and like numerals refer to like parts thereof.Bolt 160 is mounted to back plate 156 and panel 22 of FIG. 2 in likemanner. However, in this embodiment of the invention, ring 150 andgroove 151 have been eliminated in favor of restraining means in theform of bumps or protuberances 161 on the outer surface of the slots 35to 37 of lower portion 25 of bolt 160. As seen in FIG. 10, retainingring 34 has been replaced by a retaining ring 162 having a slot 163which allows ring 162 to expand and contract as it moves over the bumps161 in the slots 35 to 37. As the retaining ring 34 moves over the bumps161 (FIG. 11) and stops against the retaining ring 41 (FIG. 12), theslot 163 opens wider than shown in FIG. 10, then closes back to the FIG.10 position, and ring 34 remains trapped between back plate 156 andpanel 22 as seen in FIG. 12. The final view of bolt 160 in FIG. 12conforms to the view of the bolt 11 shown in FIG. 2.

Still another modification of bolt 11 is shown in FIGS. 13 through 16.In this embodiment, wherein again like numerals refer to like parts ofthe bolt of FIGS. 1 to 8, bolt 164 is shown having slots 35 to 37 (onlyslot 35 visible in FIG. 13). Restraining means is provided including anannular groove 165 formed on the outer surface of the lower portion 25of bolt 164 passing through slots 35 to 37. The lower end of each slot35 to 37 adjacent nose 42 is wider to form an enlarged area 166, whichmay be square-shaped as shown. It can be seen that area 166 is situatedso that slot 35 (and, of course, slots 36 and 37) passes therethroughwith groove 165 passing along the top thereof.

As seen in FIG. 14, the restraining means further includes a retainingmember 167 having a main top portion 168 with a plurality of spaceddownwardly extending generally U-shaped loops 169 to 171. Three suchloops 169 to 171 are provided corresponding, in spacing therebetween, tothe spacing between grooves 35 to 37. Also, the distance between theupper surface of portion 168 and the lower terminal end of loops 169 to171 is generally related to the distance between groove 165 and thebottom of area 166 (see FIG. 13). The spacing between the lateralextremities of each loop 169 to 171 is generally related to the width ofeach area 166. Member 167 may be of wire or other suitable material andsnap fits into groove 165, as seen in FIG. 13, with loops 169 to 171entering the area 166 associated with each groove 35 to 37. In thisembodiment, the stop ring 41 has been eliminated and its function takenup by member 167.

In operation, ring 34 (FIG. 13) moves down bolt 164 within slots 35 to37 as heretofore discussed, ears 38 to 40 entering each loop 169 to 171(as loop 169 in FIG. 13), as seen in FIG. 15, and is stopped or retainedtherein by engagement with the bottom of each loop 169 to 171, as seenin FIG. 16. Thus, member 167 traps ring 34 in place, as seen in FIG. 16,between plate 156 and panel 22, as heretofore discussed with respect toFIG. 2, and also prevents or arrests upward movement by engagement ofring 34 with member 167 (see FIG. 15). That is, the width of each ear 38to 40 is slightly less than the spacing between portions 175, 176, asshown in FIG. 15, which are resilient and spread apart when ring 34 isforced upwardly thereagainst.

In all embodiments, the bolt can remain in the upper or extractedposition shown in FIG. 2 while the panel 22 is being attached to theinstallation or otherwise held so attached thereto. In all embodiments,the ring 34 is trapped between the plate 156 and the panel 22 incounterbore 54. The plate 156 is installed by the ultimate user afterinsertion of the bolt in panel 22.

The bolt assembly described herein can be used for conventional sizediameter holes in aircraft panels. The bolt 11 has a tapered shank sothat, as soon as it is withdrawn from the panel hole, there is no loadbearing on the shank area of lesser outer diameter than the upper shankarea. Thus, the tabs 38 to 40 of ring 34 and the grooves 35 to 37 ofbolt 11 serve to maintain the advantages of known fasteners, such as theHarbison et al. fastener described and claimed in U.S. Pat. No.2,991,816, while eliminating binding that might occur between the springand bolt body of such prior art fasteners. Further, the ring 34 is asolid metallic ring and will not wear and lose its resiliency as mightthe spring 44 of the prior art Harbison et al. fastener. Since the ring34 disclosed herein does not have to expand and contract as it movesalong the differing diameter sections of the bolt body, it is notsubject to fatigue as is the Harbison et al. fastener. Applicant's ring34 is easier to manufacture and less expensive than the spring device 44of Harbison et al. Thus, applicant's ring 34 will not come off, due tothe retainer ring 41 in groove 24, whereas the Harbison et al.'s spring44 might fatigue and come off resulting in loss thereof and, possibly,sucking of the same into the engine aircraft resulting in considerabledamage. Of course, once the spring 44 of Harbison et al. is lost, thebolt itself may also shake loose and fall out of the panel in which itis installed.

Thus, rotation of the sleeve bolt 11 will cause it to threadably engagestud 15 of the receptacle assembly 12. Preferably, bolt 11 and stud 15are provided with double lead threads in order to decrease the time andmotion required to remove and install the panel. In some applications,the thickness of panel 22 and sealing requirements may necessitate theuse of gasket 50 (FIG. 2), preferably the same thickness as ring 34,between the panel 22 and sub-panel 20. Alternatively, the gasket 50 canbe eliminated. Also ring 34 may be disposed in a counterbore formed inthe upper surface of sub-panel 20, if desired.

It can be seen that I have described a quick action fastener having abolt which, when freed from engagement with the stud, is retained to theaccess panel. The bolt can remain in the up or extracted position whilethe panels are being attached to the installation, such as an aircraft.The parts are simple and easy to install. The ring 34 and ring 162 maybe quickly and easily stamped out of a metal stamping forming ears 38through 40. Thus, no careful machining of these parts is necessary.

Although a specific receptacle assembly has been described any suitablereceptacle assembly may be used.

Although I have described the fastener assembly with reference tocertain preferred embodiments, it is to be understood that the appendedclaims describe the scope of the invention and various changes andmodifications may occur to one skilled in the art without departing fromthe scope of the invention.

I claim:
 1. In a fastener assembly for joining a panel to a sub-panelcomprising a receptacle assembly having a threaded stud secured to theundersurface of the subpanel, a bolt having an enlarged head at one endand a nose at the other end, said nose being adapted to extend through acountersunk opening in said panel coaxially aligned with an opening insaid sub-panel with the stud of said receptacle assembly coaxiallyaligned with both of said openings, said bolt being threaded forthreaded engagement to said stud, the improvement which comprises:aretainer having indexing means extending inwardly toward the centrallongitudinal axis thereof; said bolt having guide means extendinglongitudinally along the outer surface thereof receiving therein saidindexing means for guiding said retainer along the body of said bolt; aplate secured to the underside of said panel trapping said retainerbetween the panel and said plate; and restraining means associated withsaid bolt for arresting the downward movement of said retainer alongsaid guide means and for stopping the upward movement of said retaineralong said guide means thereby retaining said bolt of said panel in anup or extracted position when said bolt is disengaged from said stud. 2.In the assembly of claim 1 wherein said bolt has a shank leading fromsaid enlarged head to said nose, said shank having a first outerdiameter portion adjacent said groove leading into a second outerdiameter portion, of a greater outer diameter than the outer diameter ofsaid first outer diameter portion, adjacent said head, said guide meanscomprising spaced grooves on the exterior of said shank extending fromthe terminal end of said nose, through said first-mentioned groove,through said first outer diameter portion, through said tapered portionand through a portion of said second outer diameter portion terminatingat a point spaced from said enlarged head.
 3. In the assembly of claim 2wherein at least three such last-mentioned grooves are provided.
 4. Inthe assembly of claim 3 wherein said indexing means includes at leastthree inwardly extending spaced ears riding in respective ones of saidlast-mentioned grooves.
 5. In the assembly of claim 2 wherein saidlast-mentioned grooves are of a uniform depth through said shank.
 6. Inthe assembly of claim 5 wherein said last-mentioned grooves aregenerally rectangular in cross section.
 7. In the assembly of claim 6wherein said indexing means includes a plurality of inwardly extendingears riding in said last-mentioned grooves and similarly configured. 8.In the assembly of claim 1 including friction means associated with saidbolt and said stud for preventing relative movement therebetween byproviding a lock between said bolt and said stud when said bolt isthreaded to said stud.
 9. In the assembly of claim 1 wherein saidreceptacle assembly includes a basket secured to said sub-panel, abarrel secured to said basket, said stud extending through said barreltoward said bolt and threadably engagable thereto, said barrel beingretained to said stud, and anti-rotation means associated with both saidstud and said barrel for preventing relative rotation therebetween. 10.In the assembly of claim 1 wherein said restraining means includes aprotuberance on said bolt in said guide means in the path of saidindexing means as said retainer moves along said guide means, saidrestraining means further including a ring snap-fitted into a grooveadjacent the nose of said bolt, said protuberance being spaced from saidgroove with said retainer between said protuberance and said ring whensaid bolt is in its up or extracted position.
 11. In the assembly ofclaim 10 wherein said guide means are a plurality of spaced slots, aprotuberance being provided in each of said slots and lying in the samehorizontal plane.
 12. In the assembly of claim 10 wherein said retaineris a flat split resilient washer which is adapted to spread apart atsaid split when passes over said protuberance, then return to itsoriginal condition.
 13. In the assembly of claim 1 wherein saidrestraining means includes an annular groove extending about theexterior of said bolt adjacent said nose but spaced therefrom, saidguide means being a plurality of spaced slots terminating at the lowerend adjacent said nose in an enlarged area, a resilient member having afirst upper horizontal portion mounted in said groove with a pluralityof downwardly extending vertical legs forming a plurality of U-shapedsections, each of said sections being disposed in each of said enlargedareas and generally conforming thereto, the spacing between the legsforming each of said U-shaped sections being open where said sectionsare connected to said horizontal portion, said openings being of a widthless than the width of said indexing means, said indexing means beingadapted to ride in said slots and abut against said U-shaped sections ofsaid upper horizontal portion of said member, when said bolt is in theup or extracted position and said retainer moves upwardly, and abutagainst the bottom of said U-shaped sections when said retainer movesdownwardly.
 14. In the assembly of claim 13 wherein said retainer is aflat annular washer having a central hole and said indexing means are aplurality of spaced tabs extending inwardly toward the central axis ofsaid washer and riding in said slots, the spacing between said slotsbeing related to the spacing between said tabs.